Publikationsserver der RWTH Aachen University
Modellierung der Verfestigung technischer Aluminiumlegierungen
Abstract
dc:descriptionThe large strain work hardening behaviour of technical aluminium alloys as function of the deformation temperature and strain rate is described in two ways. First a phenomenological description is made using well known models from literature. For some specific cases the models are expanded. Furthermore a new model is developed which is based on a cellular dislocation structure, taking into account four internal structure variables, namely: the mobile edge dislocation density, the mobile screw dislocation density and the sessile dislocation densities in cell interior and in cell walls. For each of these structural variables a rate equation is developed which considers detailed dislocation reactions. Therefore a significant number of physical parameters are included, that are not all familiar for the commercial Al-alloy. To facilitate the determination of these physical quantities within reasonable physical limits, an optimisation algorithm is incorporated in the model, enabling the description of macroscopic stress-strain-curves within acceptable margin of error. It is then possible with the model, to describe experimental stress-strain-curves of commercial alloys with only two physical quantities for a wide range of deformation conditions. Modelling the experimental stress-strain-curves for different deformation conditions with this new model reveals that the number of deformation-induced vacancies play an important role in describing the stress-strain-behaviour. It could be shown that the number of these deformation-induced vacancies depend on strain rate and deformation temperature.
Degree
thesis:*- Grantor dc:publisher
- Publikationsserver der RWTH Aachen University
- Year dc:date
- 2001
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Mülders, Barbara
- Contributors dc:contributor
-
- Gottstein, Günter
Subjects
dc:subject × 7Rights
dc:rights- Statement dc:rights
-
- info:eu-repo/semantics/openAccess
- Language dc:language
- ger